hi
Frequent occurance of any type of oral ulcers is related to stress too.
Vitamin D deficiency is not known to cause ulcers.It would be better to visit a dentist nearby to get clinical examination done to rule out any other causes and do the needful.You can also practo consult us for the same if needed.
Health Tips
Try warm salt water rinsing three times daily for about a week to get some relief.